The in vitro perfused rabbit ovary preparation has served as a model for the study of ovulation. It allows removal of the ovary from systemic influences, inclusion in the perfusate of agents to be evaluated for their influence upon ovulation, collection of aliquots of perfusion medium to determine biochemical alterations associated with follicular growth and rupture, direct observation of ovulation, and collection of the ova from ruptured and unruptured follicles to determine their stage of maturation. This system will be utilized to examine the effects of adrenergic agents on follicle maturation and ovulation using alpha and beta adrenergic agents. To elucidate further the role of prostaglandins in ovulation, determination of PGF and PGF2-alpha metabolite will be made on aliquots of medium. These determinations will be of particular interest in experiments in which follicles have been stimulated to maturity with PMSG. Characterization of the stage of maturation of ova ovulated under these experimental conditions is being expanded to determine the fertilizability of these ova using an in vitro fertilization technique, histologic staging, and ability of ovulated ova to mature in tissue culture. The same perfusion system with minor adaptions will be used to study ovulation in the rhesus monkey. These interrelated studies will provide basic information regarding local ovarian factors involved in the process of ovulation.